Lens-cre is active in ocular and nasal regions. AP activity is shown by the blue/purple labeling in control Lens-cre; Z/AP embryos at the indicated ages either shown in whole-mount (A,E,I,M) or in section (B,F,J,N). AP activity in Lens-cre; Z/AP; Catnblox(ex3) embryos at the indicated ages either shown in whole-mount (C,G,K,O) or in section (D,H,L,P). In O and P the arrowhead points to AP staining in the naso-lacrimal groove. Labeled structures for this and all subsequent figures are as follows: ple-presumptive lens ectoderm, ov-optic vesicle, pe-periocular ectoderm, lp-lens pit, 1ba-first branchial arch, lnp-lateral nasal process, nlg-nasolacrimal groove, oe-optic eminence, pce-presumptive corneal epithelium, lv-lens vesicle, pr-presumptive retina, pm-periocular mesenchyme, ose-ocular surface ectoderm, pcje-presumptive conjuctival epithelium, rpe-retinal pigmented epithelium, prpe-presumptive retinal pigmented epithelium, wb-whisker barrels.